The present invention relates in general to devices for connecting heat meltable materials, and in particular to a new and useful device for connecting strips of heat meltable material together or for connecting one piece of heat meltable material to another piece of heat meltable material.
Labels, such as those appearing in clothing or similar articles, are generally manufactured of thermoplastic threads such as polyester threads and the like. The labels may also be made out of a non-woven or continuous sheet of heat meltable material.
Such labels may be sewn or heat sealed to clothing.
The labels are manufactured in the form of a continuous strip from which the individual labels are cut. The strips are wound into reels and fed into a label cutting machine by use of the reels. When the end of a strip is reached, a strip from a new reel must be connected to the strip in the cutting machine to ensure continuous operation. This relatively simple requirement has long posed difficulties in this field.
In an effort to connect the end of one strip to the beginning of the next, sewing and stapling operations have been used. When using a sewing operation, a separate sewing machine is necessary. Use of staples also poses problems in that staples may damage the cutting machine and cause problems in feeding the label strips.
The most advantageous way to connect label strips of heat meltable material is to heat-seal them together. The seam formed by the heat sealing operation must be strong and the equipment for forming the seal must be adaptable to different thicknesses for the label strips. To date no satisfactory device exists for achieving this purpose.
Devices are known for heat sealing layers of heat meltable material together. U.S. Pat. No. 4,264,395 to Tota et al shows a device having pins which can be heated and pressed against the flat plate to heat seal two layers of heat meltable material together.
U.S. Pat. No. 4,094,723 to Jones discloses a film splicer which uses heat and pressure to seal strips of film together.
U.S. Pat. Nos. 3,379,595 to Bracey, Jr. and 3,033,257 to Weber also show devices for heat sealing thermoplastic materials.